Rotary core barrel and drilling bit



Sept. 14, 1926.

H. C. SMITH ROTARY CORE BARREL AND DRILLING BIT Fild June 22, 1925 BY max aw A TTGRNE Patented Sept. 14,;1926.

UNITED STATES PATENT orr ics.

immrm c. sinrn, or wmrmn, chmroam norms! 001m BARREL AND DRILLING an".

Application filed im 2a, 1925. swarm. 38,654.

This invention relates to a tool for earth boring and pertains more particularly to a rotary hydraulic boring tool having lateral cutting blades. In tools of this character,

I it is common practice to'em loy two dia- -metrically opposite 'fish tail lades. Such a' tool advances through the formation rapidly and is efiicient in this respect.

However, twoblades do not. keep the tool 10 centered -in the hole, the tool wabbling and producing a hole which is not round.-

If more than two blades are GIIIPlOYGiLlt "is found that the tool does not bite into the I formation as rapidly. Efiiciency of the 1 tool in makin hole is decreased, 'but the tool is maintained in centered alignment.

ing' cut-ting teeth to form a crown'cutter' 8. There are two cutter blades and interposed between the blades and extending from the 65 body are ribs 9, the outer edges of the ribs lying in the periphery of the circle passing through the outer ends of the: cutters. These -ribs may incidentally aid in trimung the side wall of-the hole, but their primary purpose is that of maintaining the toolcentere They do not serve to advance the hole, and the lower edges are shown spaced a considerable distance above the lower cutting ed e's-'-'of the blades. An

overhanging spaced s oulder 10 is provided oif the body. 'This shoulder-is spaced above he r1bs and cutter blades for a purpose later Increasing the diameter of the body -or recferredito.-

stockofthe tool above the cutter blades aids in. maintaining the tool centered but inter my invention illustrated in the accompany ing drawing, in which:

Fig. 1is an axial section through a complete tool; Fig. 2 is a fragmentary view in elevation of the tool; Ei 3 is a section as seen on the line 3'3 of ig. ,1; and Fig. 4 is a section as seen on the hue 44 of Fig.

The invention is shown embodied in a tool adapted to take cores whereby the formation may be sanrpled. The present vinvention is especiallya apt'ed to a tool of this character, but-lnot'limited thereto...--

The body '5 of" the tool istapered on the interior toward the bottom, therebeing a bore therethrough as indicated byf 6. EX- tending from'the body and radially thereof are cutter blades 7, which blades are flush with the mouth of the bore, the latterhav- The upper portion of the body indicated by 11 is provided'with a socket having a tapered threaded'bore 12. The bottom of the socket is of larger diameter than the bore 6 of the body so that a water or slush space is provided. The bore 6 at the upper. end is threaded and receives a retainer tube. 13; Mounted upon the top of the retainer tube is a valve structure 14 having a check valve which permits passage of fluid from the retainer tube but not into the retainer '80 tube. Threaded into the box .11 is an adapter 15 having a bore of reater internal diameter than that of the iameter of retainer tube 13 so as toprovide anannular space about the retainer tube. The upper 86 end of-the' adapter is internally threaded to receive a barrel 16. Secured to the. top of v the barrel is a fitting 17 having a tapered box adapted to receive a pin of a tool oint, whereby the tool may be connected to the drill pipe. Ports 18.1ead from: the. water chamber in box '11,'to the lower face of the 9 so asto wash thereover.

'shoulder'10and above the blades 7 and ribs "The construction is such that the wash liquid; is delivered to the, blades and ribs and washes over the faces thereof; The ribs 9 do not interfere with the circulationof the wash, and the cuttings donot ball up in front of the blades or 'ribs The cuttings may pass upwardly 'into. the" space between the shoulder and blades thereby the space therebetween. Itwill be noticed that. I only two blades may be ,u sed,.'and yetthe ribs will maintain the tool cente'red'during operation without'interference with the circulation. While'the structure is especially adapted for a tool employing two cutter blades, yet it is not limited to this number. What I claim is: i I 1. In a rotary boring tool, a body, laterally extending. cutter blades thereon, and ribs interposed between and 1n row with an overhanging ledgefwith water courses opening therethrough for irectingcirculation fluid axially downward, laterally ex.- tending cutter blades on said body below said ledge and spaced therefrom, and ribs on said body interposed between and in row with said blades, said ribs being spaced from said ledge and ending on their lower edges short of the cutting edges of said blades.

,4. In a rotary boring tool, a body havingan overhanging ledge with water courses opening therethrough for directing circulation fluid axially 'downward,.laterally ex tending-cutter blades on said body spaced below said ledge. ribs onsaid body projecting radially substantially the same distance .as said blades, said ribs being spaced below said ledge between and ending short of the' cutting edges of said blades so as toaid the latter in maintaining said tool centered'during cutting operation.

5. In a rotary boring tool, a body having an overhanging ledge with water courses opening therethrough for directing circulation fluid axially downward, a pair of .fish tail blades on opposite sides of said body vdisposed below said ledge and separated therefrom, and ribs interposed between and in row with said blades and projecting laterally fromsaid body a radial distance sub-- stantially equal to the radial distance of said blades, said ribs being separated from said ledge 'and ending short of the cutting edges of said blades.

6. In a rotary boring tool, a 'b ody having a 'centraltubular core bit, laterally extending cutter blades on said body, and ribs on said body lnterposed between and in'row with 66 said blades and ending on their lower edges short of thecutt'ing edges of said blades.-

7. In a rotary boring tool, a body having a central tubular core bit, a pair of fish tail blades on opposite sides of said body, and

ribs interposed between said blades-and projecting laterally from said body (a; radial distance substantially equal to the radial distance of said blades, said ribs ending short of the cutting edges of said blades.

8. In a rotary boring tool, a body having a central tubular core with a crown cutter at the lower end thereof,-laterally extending cutter bladesthereon having their cutting edges flush with-the edge of said crown cutter, and ribs on said body interposed between .said blades and ending on their lower, edges short of the cutting edges of said bla/des.

9. In a rotary boring tool, a body having a central tubular core'anda crown cutter,

laterally extending cutter blades on said body having their edges flush with'theledge of said crown cutter, ribs 011 said body pro jectin g. radially substantially the. same dis- 'tance as said blades and ending short ofthe cutting edges thereof so as to aid said blades in maintaining said tool, centered during cutting operation.

10. In a rotary a central tubular coreprovided with a crown boring tool, a body having cutter at the lower edge, a pair of fishtail blades on opposite sides of said body and having their cuttingedges flush with the edge of said crown cutter, and ribs interposed between said blades and projecting laterally from saidbody a radial distance substantially equal to the radial distance of said blades, said ribs ending short of the. cutting edges ofsaid blades.

11. In a rotary boring tool, a body hav ing acentral tubular core ending in a crown cutter and provided at the upper portion thereof with an overhanging ledge provided i with water courses opening thereth'rough for directing eirculatibn fluid axially downward,

laterally extending cutter blades on saidbody having their cutter edges ending flush withthe edge of said crown cutter, and ribs on said body interposed between said blades and ending on their lower edges short of the cutting edges of said blades.

v12. In a rotary boring tool, a body hav rie ing a central tubular core'ending in a crown cutter and provided at the upper portion thereof withan overhanging ledge having ing water courses opening therethrough for directing circulation fluid axially downward laterally extending cutter blades thereon,

:ribs on said body projecting radially sub;

stantially the same distanceas said blades and ending short of the cutting edges thereof so as to aid said blades in maintaining said tool centered during cutting operation, the upper edges of said blades and ribs being 'spaced from said ledge and the cutting edges of said blades being flush with the edge of said crown cutter.. y

13. In a rotary boring tool, 'a body having a central tubular cor'e ending in a crown cutter and provided at )the upper portionthereof with an overhanging ledgehaving water courses opening therethrough for directihg circulation iluid axially downwardto the radial distance of said blades, said ly, a 'pair of fish tail blades on opposite sides ribs being separated from said ledge and 10 of said body, said blades being separated at ending short of the cutting edges of said their upper edges from-said ledge and havblades.

ing their cutting edge flush with said crown In Witness that I claim the foregoing I cutter, and ribs interposed between said have hereunto subscribed my name this 12th blades and projecting laterally from said day of June,1925. body a radial distance substantially equal HERMAN C. SMITH. 

